Karl Popper’s philosophy of science draws a clear line between his critical rationalism, framed around problems, tentative theories, and error elimination, and the classical hypothesis-confirmation schema. In the traditional view, the scientific process is structured as follows: a hypothesis is formulated, experiments are conducted, and the goal is to accumulate evidence that supports the hypothesis until it becomes a thesis. According to this model, scientific progress is primarily incremental and confirmatory; the central aim is to verify hypotheses and establish enduring truths.

Popper rejects this model, insisting that scientific knowledge is never conclusively verified, only provisionally held until falsified. For Popper, the scientific enterprise begins with a problem (or anomaly), producing a tentative solution (conjecture) which must then be rigorously tested through attempts to refute it. Error detection and correction are core mechanisms; every surviving theory is subject to ongoing critical scrutiny. In Popper’s schema, science advances not by collecting confirmations but by actively seeking out refutations—by exposing theories to the risk of falsification through empirical trials.​

Popper’s explanation for this shift is foundational: “The criterion of the scientific status of a theory is its falsifiability, or refutability, or testability.” Scientific inquiry, he argues, is defined by its openness to criticism and revision. There is no such thing as a final truth in science—only a continual cycle of problems, provisional solutions, and criticism, each stage feeding the next. If researchers only seek confirmation, they risk entrenching dogma and failing to identify weaknesses in their theories. Science, therefore, must value the process of conjecture and refutation, not the accumulation of permanent truths